1. Technical Field
The present invention relates to inflatable vehicle seat belt webbing. In particular, the present invention relates to a fluid source for inflating a length of vehicle seat belt webbing.
2. Description of the Prior Art
A typical vehicle seat belt system includes a length of belt webbing wound on a spool of a seat belt webbing retractor. The belt webbing is extensible about a vehicle occupant to restrain the occupant. The belt webbing spool rotates in a belt withdrawal direction as the occupant withdraws belt webbing from the retractor. A rewind spring is connected with the belt webbing spool and biases the belt webbing spool for rotation in an opposite belt retraction direction.
It is known to use a pyrotechnic device, such as a gas generating initiator, to provide fluid under pressure for inflating a bladder within the belt webbing during a vehicle collision. The fluid is used to transform a portion of the belt webbing into a cushion for tensioning the belt webbing against the occupant and increasing the surface area over which the force with which the belt webbing restrains the occupant during the collision is applied. The bladder may also emerge from the seat belt to act as a secondary air bag device.
The present invention is a vehicle seat belt system comprising a seat belt for helping to protect a vehicle occupant. The seat belt includes an inflatable portion. The system further comprises at least one microelectromechanical device (MEMS device) connected in fluid communication with the inflatable portion of the seat belt and energizable to supply inflation fluid to inflate the inflatable portion of the seat belt.